Wheel bearing units of this type are used, in particular, to mount the nondriven wheels of motor vehicles. They are designed in such a way that they can absorb the loads which occur during operation, for example the radial load which is caused by the vehicle weight and the tilting moments about a perpendicular axis with respect to the wheel bearing axis, which tilting moments occur, for example, when driving around bends. In the case of a appropriate design of the rolling body rows, for example, as angular contact roller bearings or as angular contact ball bearings, said wheel bearing units are also capable of absorbing the axial forces which occur during operation.
The website kfz-tech.de/Radlager.htm shows a typical wheel bearing unit of the type which is mentioned in the preamble of claim 1, with an outer rolling body row which is close to the wheel flange and an inner rolling body row which is remote from the wheel flange. The structural stipulations, that is to say the dimensions of a bearing journal and of the wheel hub which is adapted to the largely standardized wheel rims, but also questions of part store management at the manufacturer and spare part store management at the repair company in effect suggest to configure the two rolling body rows identically. However, on account of their different spacing from the wheel flange, the two rolling body rows are loaded differently by the moments and forces which are introduced into the wheel bearing unit via said wheel flange, with the result that they are subjected to different wear and therefore have a different service life. Wheel bearing units of this type therefore already have to be replaced when the less loaded rolling body row has not yet reached the end of its theoretically possible service life.